3649-08 IICB.indd - Faculty of Biological Sciences - University of ...

Stefan Kepinski
RCUK independent research fellow (2006-);
Bsc.Hons (Liverpool);
PhD. (Liverpool)
Contact: s.kepinski@leeds.ac.uk
Auxin and
plant development
I am interested in understanding how
the plant hormone auxin operates
throughout plant development to
shape the plant and control important
traits. Auxin is a fascinating signalling
molecule because of the sheer diversity
of plant developmental processes in
which it is involved.
At the cellular level, auxin can regulate
cell division, cell expansion and can
trigger specific differentiation events.
In addition, auxin is unique among
plant hormones in that its transport
is both tightly regulated and polar,
allowing auxin to carry directional
intercellular and long distance signals,
and thus act as a regulator of pattern
formation. A central component of
this developmental control is the
transcriptional regulation of hundreds
of genes and we are focussing
on precisely how auxin regulates
gene expression. Using a range of
biochemical and genetic techniques we
have recently made significant progress
in understanding the early events
of auxin signalling by identifying the
receptor for this response and thereby
completing a basic signal transduction
cascade from auxin to changes in gene
expression. As well as understanding
better the biology of auxin perception,
we are also studying how this entire
mechanism is then used throughout
the plant to regulate a range of very
different developmental processes.
This addresses the apparent paradox
of how the perception of auxin as a
single signalling molecule can generate
diverse response outputs, specific to
particular developmental contexts.
This work involves a systematic
analysis of the auxin signalling
components in hand coupled to
novel genetic and chemical genetic
screens to identify new components
modulating auxin response.
Funding for this work comes from the
BBSRC and Umeå University, Sweden
More information:
http://www.fbs.leeds.ac.uk/staff/profile.
php?tag=Kepinski_S
Representative Publications
Kepinski, S. (2006) Integrating hormone
signalling and patterning mechanisms in plant
development. Current Opinion in Plant Biology
9: 28-34
Kepinski, S and Leyser, O. (2005) The
Arabidopsis F-box protein TIR1 is an auxin
receptor. Nature 435: 446-451
Kepinski, S and Leyser, O. (2004) Auxininduced
SCF TIR1 -Aux/IAA interaction involves
stable modification of the SCF TIR1 complex.
Proceedings of the National Academy of
Science, USA 101: 12381-12386
Gray, WM†, Kepinski, S†, Rouse, D, Leyser,
O, and Estelle, M. (2001) Auxin regulates
SCF TIR1 -dependent degradation of Aux/IAA
proteins. Nature 414: 271-276